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The combinations shown in a sail-plan almost always include
three configurations:

A light air sail plan. Over most of the Earth, most of
the time, the wind force is Force 1 or less. Thus a sail plan should
include a set of huge, lightweight sails that will keep the ship
underway in light breezes.

A working sail plan. This is the set of sails that are
changed rapidly in variable conditions. They are much stronger than
the light air sails, but still lightweight. An economical sail in
this set will include several sets of reefing ties, so the area of
the sail can be reduced in a stronger wind.

A storm sail plan. This is the set of very small, very
rugged sails flown in a gale, to keep the vessel under way and in
control.

In all sail plans, the architect attempts to balance the force
of the sails against the drag of the underwater keel in such a way that the vessel naturally
points into the wind. In this way, if control is lost, the vessel
will avoid broaching (turning edge-to-the wind), and being beaten
by breaking waves. Broaching always causes uncomfortable motion,
and in a storm, the breaking waves can destroy a lightly-built
boat.

The architect also tries to balance the wind force on each sail
plan against a range of loads and ballast. The calculation assures
that the sail will not knock the vessel sideways with its mast in the
water, a capsize and possible sinking.

Contents

Terminology

Types of
sail

A fore
and aft sail is one that, when flat, runs fore and aft.
These types of sails are the easiest to manage, because they often
do not need to be relaid when the ship changes course.

A gaff rigged
sail is a fore-and-aft sail shaped like a truncated triangle the
upper edge of which is made fast to a spar called a gaff. The top
of the gaff rigged sail tends to twist away from the wind reducing
its efficiency when close-hauled. However, due to the gaff on the
top edge of the sail the center of effort is typically lower,
somewhat reducing the angle of heel (leaning of the boat caused by
wind force on the sails) compared to a similar sized Bermuda rigged
sail.

A square
sail is set square to the mast from a yard, a spar running
transversely in relation to the hull (athwartships). It is not, as
commonly thought, named after the approximate shape of the sail, it
is named for the square angle between the sail and the mast. In the
olden days design of a square rigger, sailors would have to climb
the rigging and walk out on
"footropes" under the yard to furl and unfurl the sails.
In a modern square rigged design the crew can furl and unfurl its
sails by remote control from the deck. Some cruising craft with
fore-and-aft sails will carry a small square sail with top and
bottom yards that are easily rigged and hauled up from the deck
(not requiring climbing the mast); such a sail is used as the only
sail when running downwind under storm conditions, as the vessel
becomes much easier to handle than under its usual sails, even if
they are severely reefed (shortened).

A lateen sail is
a triangle with one or two sides attached to a wooden pole. This is
one of the lowest drag (the sailing term is windage)
sails, and it is not easy to manage.

A Bermuda or Marconi sail is a
triangular sail with one point going straight up.

A staysail
("stays'l") is a piece of cloth that has one or two sides attached
to a stay, that is, one of the ropes or wires that helps
hold the mast in place. A staysail was classically attached to the
stay with wooden or steel hoops. Sailors would test the hoops by
climbing on them.

A jib is a staysail
that flies in front of the foremost vertical mast.

A spanker is a
gaff-sail flown on the mizzenmast of a tall ship. For ease of handling in large sail
plans, these sails would sometimes be split into lower and upper
spankers.

Order

The standard terminology assumes three masts, from front to
back, the fore-mast, main-mast and mizzen-mast. On ships with fewer
than three masts, the tallest is the main-mast. Ships with more
masts number them.

From bottom to top, the sails of each mast are named by the mast
and position on the mast, e.g. for the mainmast, from lowest to
highest: main course, main
topsail, main topgallant
("t'gallant"), main royal, main skysail, and main moonraker. Since the early twentieth century,
the topsails and topgallants are often split into a lower and an
upper sail to allow them to be more easily handled.

On many warships, sails above the fighting top (a platform just
above the lowest sail) were mounted on separate masts ("topmasts"
or "topgallant masts") held in wooden sockets called "tabernacles".
These masts and their stays could be rigged or struck as the
weather and tactical situation demanded.

In light breezes, the working square sails would be supplemented
by studding
sails ("stuns'l") out on the ends of the yardarms. These
were called as a regular sail, with the addition of "studding". For
example, the main top studding sail.

The staysails between the masts are named from the sail
immediately below the highest attachment point of the stay holding
up the staysail. Thus, the mizzen topgallant staysail can be found
dangling from the stay leading from above the mizzen (third) mast's
topgallant sail to some place (usually two sails down) on the
second (main) mast.

The jibs, staysails between the first mast and the bowsprit were named
(from inner to outer most) fore topmast staysail (or foretop stay),
inner jib, outer jib and flying jib. All of the jib's stays meet
the foremast just above the fore topgallant. Unusually, a fore
royal staysail may also be set.

Ropes

Ropes were classically made of manila, cotton, hemp,
or jute; papyrus (in ancient Egypt) and coir have also been seen. They are now made of stainless steel
(301), galvanized steel, polyester
(Dacron), polyamides (nylon), and sometimes crystallized
hydrocarbons (Kevlar and Spectra).

Rigging

Standing rigging does not change
position. Usually it braces the masts.

A sheet is a line used to adjust the
position of a sail so that it catches the wind properly.

Halyards are
the lines on which one pulls to hoist something; e.g. the
main-topgallant-staysail-halyard would be the line on which one
pulls to hoist (unfurl) the main-topgallant-staysail.

A block is the seaman's name for a
pulley-block. It may be fixed to some part of the vessel or spars,
or even tied to the end of a line.

The sheave is the wheel within a block, or a spar,
over which a line is rove.

A fiddle block has two or more sheaves in one block,
each with its own axle, so the sheaves are aligned.

A snatch-block can be closed around a line, to grab
the line, rather than threading the end of the line through the
block.

A shackle is a
piece of metal to attach two ropes, or a block to a rope, or a sail
to a rope. Customarily, a shackle has a screw-in pin which
often is so tight that a shackle-key must be used to
unscrew it. A snap-shackle does not screw, and can be
released by hand, but it is usually less strong or more expensive
than a regular shackle.

Running lines are made fast (unmoving) by
belaying them to (wrapping them around) a cleat or a
belaying-pin located in a pin-rail.

Sprit and
stays

Bowsprit, a
horizontal spar extending from the bow (front) of the boat used to
attach the forestay to the foremost mast

Bobstays, a pair of stays on either side of the
bowsprit bracing it against lateral forces

martingale, a heavy stay directly
below the bowsprit, often the strongest on a ship, frequently made
of chain. Between the bowsprit and the martingale ran a heavy pole
to provide tension known colloquially as the dolphin
striker.

The stays on a ship roughly form hoops of tension holding the
masts up against the wind. Many ships have been "tuned" by
tightening the rigging in one area, and loosening it in others. The
tuning can create most of the stress on the stays in some
ships.

Types of
ships

Depending on which sails are used, a boat can have several names
(eg barquentine, brig, ...)

Sloop: a Bermuda or gaffmainsail lifted by a single mast with a
single jib bent onto the forestay, held taut with a backstay. The mainsail is
usually managed with a spar on the
underside called a "boom." One of the best-performing rigs per square foot of sail area and
is fast for up-wind passages. This rig is the most popular for
recreational boating because of its potential for high performance.
On small boats, it can be a simple rig. On larger sloops, the large sails have high loads, and one
must manage them with winches or multiple purchase
block-and-tackles.

Cutter: like a sloop with two jibs
(a staysail and a yankee) in the foretriangle. Better than a sloop
for light winds, it is also easier to manage. It has slightly less
up-wind ability than a sloop because it has more windage.

Yawl: like a
sloop or catboat with a mizzen mast located aft (closer to the
stern of the vessel) of the rudder post. The mizzen is small, and
is intended to help provide helm balance.

Ketch: like
a yawl, but the mizzenmast is often much larger, and is located
forward of the rudder post. The purpose of the mizzen sail in a
ketch rig, unlike the yawl rig, is to provide drive to the hull. A
ketch rig allows for shorter sails than a sloop with the same sail
area, resulting in a lower center of sail and less overturning
momentum. The shorter masts therefore reduce the amount of ballast
and stress on the rigging needed to keep the boat upright.
Generally the rig is safer and less prone to broaching or
capsize
than a comparable sloop, and has more flexibility in sailplan when
reducing sail under strong crosswind conditions—the mainsail can be
brought down entirely (not requiring reefing) and the remaining rig
will be both balanced on the helm and capable of driving the boat.
The ketch is a classic small cargo boat.

Catboat: a sailboat with a single mast
and single sail, usually gaff-rigged. This is the easiest sail-plan
to sail, and is used on the smallest and simplest boats. The
catboat is a classic fishing boat. A popular movement among
home-built boats uses this simple rig to make "folk-boats." One of
the advantages of this type is that it can be rigged with no boom
to hit one's head or knock one into the water. However, the gaff
requires two halyards and often two topping lifts. The weight of
the gaff spar high in the rigging can be undesirable. The gaff's
fork (jaws) is held on by a rope threaded through beads
called trucks (US) or parrel beads (UK). The gaff must
slide down the mast, and therefore prevents any stays from bracing
the mast. This usually makes the rig even heavier, requiring yet
more ballast.

Gunter: a
rig designed for smaller boats where the mast is often taken down.
It consists of a relatively short mast (usually slightly shorter
than the boat so that it can be stowed inside) and a long gaff
(often only slightly shorter than the mast). However, rather than
the usual trapezoidal shape of a gaff sail, it is triangular, like
a Bermuda rig. This allows the gaff, when hoisted, to pivot upwards
until it is vertical, effectively forming an extension to the mast.
Thus a decent-sized sailing rig can be added to the boat while
still allowing all the equipment to be stowed completely inside it.
The popular Mirror class of dinghy is gunter rigged for this
reason.

Schooner: a fore-and-aft rig having
at least two masts, with a foremast that is usually smaller than
the other masts. Schooners have traditionally been gaff-rigged and
in small craft are generally two-masted, however many have been
built with Marconi rigs (and even junk rigs) rather than gaffs and
in the golden age of sail, vessels were built with as many as seven
masts. One of the easiest types to sail, but performs poorly to
windward without gaff topsails. The extra sails and ease of the
gaff sails make the rig easier to operate, though not necessarily
faster, than a sloop on all points of sail other than up-wind.
Schooners were more popular than sloops prior to the upsurge in
recreational boating. The better performance of the sloop upwind
was outweighed for most sailors by the better performance of the
schooner at all other, more comfortable, points of sail. Advances
in design and equipment over the last hundred years have diminished
the advantages of the schooner rig. Many schooners sailing today
are either reproductions or replicas of famous schooners of
old.

Brigantine: two masts,
square-rigged on the foremast and fore-and-aft rigged on the
mainmast.

Barquentine: is a three masted
vessel, square rigged on the foremast and fore-and-aft rigged on
the main and mizzen masts. Some sailors who have sailed on them say
it is a poor-handling compromise between a barque and a ship,
though having more speed than a barque or schooner.

Barque:
three masts or more, square rigged on all except the aftmost mast.
Usually three or four masted but five masted barques have been
built. Lower-speed, especially downwind, but requiring fewer
sailors than a ship. This is a classic slow-cargo ship.

Fully rigged Ship: three or more
masts, square rigged on all, with stay-sails between. The classic
ship rig originally had exactly three masts, but four and
five masted ships were also built. The classic sailing warship—the
ship of the
line—was fully rigged in this way, because of high
performance on all points of wind. They were larger than brigs and
brigantines, and faster than barques or barquentines, but required
more sailors.

Bragana or felucca: a classic in the
Mediterranean or Indian Ocean. Three lateen sails in a row.

Polacre: a three master with a
narrow hull; carrying a square-rigged foremast, followed by two
lateen sails. The same vessel, if she substituted her square-rigged
mast with another lateen rigged one, would be called a xebec.

Junk: the standard Chinese design:
Elliptical sails made flat with bamboo inserts (battens),
permitting them to sail well on any point of sail. Easy to sail,
and reasonably fast. The nature of the rig places no extreme loads
anywhere on the sail or rigging, thus can be built using
light-weight, less expensive materials. Some of the largest sailing
ships ever constructed were junks for the Chinese treasure fleets.
Junks also customarily had internal water-tight rooms, kept so by
not having doors between them. Usually they were constructed of teak or mahogany.